is used by telecommunications companies to transmit telephone signals, Internet communication and cable television signals. It is also used in other industries, including medical, defense, government, industrial and commercial. In addition to serving the purposes of telecommunications, it is used as light guides, for imaging tools, lasers, hydrophones for seismic waves, SONAR, and as sensors to measure pressure and temperature.
[pdf] A high-occupancy toll lane (HOT lane) is a type of or that is available to and other exempt vehicles without charge; other vehicles are required to pay a that is adjusted in response to demand. Unlike, drivers have an option to use general purpose lanes, on which a fee is not charged. Express toll lanes, which are less common, operate along similar lines, but.
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